17 April 2014 Highly-efficient high-power pulsed CO2 laser characterized by transverse-flow laser amplifiers
Author Affiliations +
In this paper, we provide a detailed review of development of a highly-efficient high-power nanosecond pulse CO2 laser using transverse-flow radio-frequency (RF)-exited laser amplifiers, which is for extreme ultraviolet (EUV) light source of a next generation of nano-lithography. High-density excited high-power transverse-flow CO2 lasers were designed and built for the application of laser produced plasma (LPP) EUV source. We carried out an amplification test of the transverse-flow CO2 laser seeded by a nanosecond pulse CO2 laser. A four-amplifier system generated an average output power of 21 kW with an electrical input power of 400 kW for discharges. The electrical-to-optical efficiency was 5.2%. The input pulse laser had an average power of 46 W, the repetition rate was 100 kHz, and the pulse duration was 15 ns. The transverse-flow CO2 laser has strong points in high gain and availability of the multi-fold optical path. A highly-efficient amplification was experimentally proved characterized by transverse-flow CO2 laser amplifiers even with low-power seed. A transverse-flow CO2 laser is a promising candidate for an amplifier in the LPP EUV light source.
© (2014) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Yoichi Tanino, Yoichi Tanino, Jun-ichi Nishimae, Jun-ichi Nishimae, Tatsuya Yamamoto, Tatsuya Yamamoto, Taichiro Tamida, Taichiro Tamida, Koji Funaoka, Koji Funaoka, Shuichi Fujikawa, Shuichi Fujikawa, "Highly-efficient high-power pulsed CO2 laser characterized by transverse-flow laser amplifiers", Proc. SPIE 9048, Extreme Ultraviolet (EUV) Lithography V, 90480E (17 April 2014); doi: 10.1117/12.2045566; https://doi.org/10.1117/12.2045566

Back to Top